Reversibility of Acute Adrenal Insufficiency After Hip Replacement: A Case Series

Acute adrenal insufficiency is a rare but potentially lethal condition, that is important to identify promptly and treat with replacement therapy. It can be consequent to adrenal hemorrhage that can occur after major orthopedic surgery. Few data are available about potential recovery of adrenal function, as well as both timing and modality of cortisone acetate withdrawal, probably due to the assumption that adrenal failure should be definitive. The extension of adrenal damage can be different, so justifying a partial, or potentially complete, recovery of adrenal function. The aim of our article is to highlight the opportunity of a periodical revaluation of adrenal reserve in order to identify those patients which are able to interrupt replacement therapy.

We had recently described one case of acute adrenal insufficiency, which developed short time after hip replacement; the patient was able to discontinue cortisone acetate treatment 46 months after the diagnosis and remained untreated up to five years later. We collected other two cases of acute adrenal insufficiency, developed about one week after major orthopedic surgery. We followed such patients for about three years, repeatedly reassessing adrenal imaging and cortisol response to 250 μg ACTH test, in order to ascertain the real need of lifetime substitutive treatment with cortisone acetate. Acute adrenal insufficiency partially reverted during the follow up for both patients. We observed a reduction in adrenal glands' volume and a progressive improvement of cortisol basal levels, without response (or with a poor one) to ACTH stimulation, as well as with ACTH basal levels persistently above the normal range after 36 and 28 months respectively spent from the acute event.

The present finding suggests the opportunity that patients developing acute adrenal insufficiency after major orthopedic surgery undergo long-term surveillance, in order to establish if steroid replacement has to be continued, or it can be safely withdrawn.